The reason why lung cancer is increasing in non-smokers and never-smokers isn’t entirely clear.
How Common Is Lung Cancer in Never-Smokers?
Surgeon General first linked cigarettes to cancer).
Verywell / Luyi Wang
Who Is at Risk of Lung Cancer Among Never-Smokers?
Studies have shown that two groups of never-smokers are especially vulnerable to lung cancer: females and Asian people.
Statistically, female never-smokers are more than twice as likely as male never-smokers to get lung cancer.
In total, around two-thirds of all cases involve women.
This is despite the fact that U.S. men represent over 80% of lung cancer cases overall.
Never-smokers also differ in that they almost exclusively develop a throw in of cancer called lungadenocarcinoma.
These include theEGFR,Ki-67,andHTERTmutations commonly seen in smokers, andp-AKTandp27mutations common in never-smokers.
There also appear to be differences in how cancer-causing mutations develop.
With never-smokers, many of these mutations may already be present at birth.
As such, fewer acquired mutations may be needed for cells to turn malignant.
This may explain in part why never-smokers tend to get lung cancer at an earlier age than smokers.
In theory, cancerous mutations may develop spontaneously in someone who is genetically predisposed to the disease.
Secondhand Smoke
Secondhand smoke is the tobacco smoke you inhale from another persons cigarette or cigar.
It is estimated that over 7,000 lung cancer deaths occur in the U.S. due to secondhand smoke.
It is also possible to get exposed tothirdhand smoke.
Children who crawl on contaminated floors and carpets are especially vulnerable.
Traffic police and long-distance drivers are at high risk of exposure to air pollution and car fumes.
The high temperatures used for stir-frying in Chinese cooking can oxidize and aerosolize the oil.
These include:
Other tests likesputum cytologyorendobronchial ultrasoundcan be performed if imaging studies are negative or inconclusive.
Females and Asian people are at greatest risk.
The cause of lung cancer in never-smokers is poorly understood, but genetics is thought to play a part.
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